Tibet consists of high table-lands without vegetation, with here and
there snowy peaks and barren ravines, torrents fed by glaciers,
depressions with glittering beds of salt, lakes surrounded by
luxurious forests, with icy winds sweeping over all.

The barometer indicated an altitude of thirteen thousand feet above
the level of the sea. At that height the temperature, although it was
in the warmest months of the northern hemisphere, was only a little
above freezing. This cold, combined with the speed of the
"Albatross," made the voyage somewhat trying, and although the
friends had warm traveling wraps, they preferred to keep to their
cabin.

It need hardly be said that to keep the aeronef in this rarefied
atmosphere the suspensory screws had to be driven at extreme speed.
But they worked with perfect regularity, and the sound of their wings
almost acted as a lullaby.

During this day, appearing from below about the size of a carrier
pigeon, she passed over Garlock, a town of western Tibet, the capital
of the province of Cari Khorsum.

On the 27th of June, Uncle Prudent and Phil Evans sighted an enormous
barrier, broken here and there by several peaks, lost in the snows
that bounded the horizon.

Leaning against the fore-cabin, so as to keep their places
notwithstanding the speed of the ship, they watched these colossal
masses, which seemed to be running away from the aeronef.

"The Himalayas, evidently," said Phil Evans; "and probably Robur is
going round their base, so as to pass into India."

"So much the worse," answered Uncle Prudent. "On that immense
territory we shall perhaps be able to --"

"Unless he goes round by Burma to the east, or Nepal to the West."

"Anyhow, I defy him to go through them."

"Indeed!" said a voice.

The next day, the 28th of June, the "Albatross" was in front of the
huge mass above the province of Zang. On the other side of the chain
was the province of Nepal. These ranges block the road into India
from the north. The two northern ones, between which the aeronef was
gliding like a ship between enormous reefs are the first steps of the
Central Asian barrier. The first was the Kuen Lung, the other the
Karakorum, bordering the longitudinal valley parallel to the
Himalayas, from which the Indus flows to the west and the
Brahmapootra to the east.

What a superb orographical system! More than two hundred summits have
been measured, seventeen of which exceed twenty-five thousand feet.
In front of the "Albatross," at a height of twenty-nine thousand
feet, towered Mount Everest. To the right was Dhawalagiri, reaching
twenty-six thousand eight hundred feet, and relegated to second place
since the measurement of Mount Everest.

Evidently Robur did not intend to go over the top of these peaks; but
probably he knew the passes of the Himalayas, among others that of
Ibi Ganim, which the brothers Schlagintweit traversed in 1856 at a
height of twenty-two thousand feet. And towards it he went.

Several hours of palpitation, becoming quite painful followed; and
although the rarefaction of the air was not such as to necessitate
recourse being had to the special apparatus for renewing oxygen in
the cabins, the cold was excessive.

Robur stood in the bow, his sturdy figure wrapped in a great-coat. He
gave the orders, while Tom Turner was at the helm. The engineer kept
an attentive watch on his batteries, the acid in which fortunately
ran no risk of congelation. The screws, running at the full strength
of the current, gave forth a note of intense shrillness in spite of
the trifling density of the air. The barometer showed twenty-three
thousand feet in altitude.

Magnificent was the grouping of the chaos of mountains! Everywhere
were brilliant white summits. There were no lakes, but glaciers
descending ten thousand feet towards the base. There was no herbage,
only a few phanerogams on the limit of vegetable life. Down on the
lower flanks of the range were splendid forests of pines and cedars.
Here were none of the gigantic ferns and interminable parasites
stretching from tree to tree as in the thickets of the jungle.